Archery bow



N. KAPPAS ARCHERY BOW Jan. 26, 1965 2 Sheets-Sheet 1 Filed NOV. 10, 1961 Jan. 26, 1965 N. KAPPAS $187,063

ARCHERY BOW Filed Nov. 10. 1961 2 Sheets-Sheet 2 fnl/ezzzf'orx Mb? x75 0 as; {y WLZM United States Patent O 3,167,063 ARQHERY BfBW Nick Kappas, -69 Rhode Island, Gary, Ind, assignor of one-half to Ula R. Knight and one-fourth to Lawrenc Kappas, both of Lake Qounty, Ind.

Filed Nov. ill, 1% No. 151,533 9 Claims. (Qt. i2d-23) This invention relates generally to archery bows, and more particularly to the core of a laminated bow.

Modem archery bows are generally of laminated construction, comprising an inner core formed of wood with laminations of plastic material, commonly fiber glassreinforced resin, adhered to the front and back sides. In conventional laminate/d bow constructions, the core itself has been formed of at least two wood laminations glued together which result in a tendency for the ends of the core to set up out of tiller or to twist. In bows of the recurve type, it has generally been found necessary to add additional wood or plastic laminations at the recurves to prevent them from going out of tiller and further to prevent chrysal at the recurve, i.e., degeneration of the glue and separation of the laminations due to constant flexing. The addition of material at the recurves, however, reduces the working of the recurves, i.e., the resilience and ability to flex, thus transferring a substantial part of the bending or flexing to the limbs and in turn transmitting the shock of release to the grip.

It is therefore desirable to provide a laminated archery bow construction in which a wood core having only a single thickness is employed and in which additional ma terial need not be added at the recurves, thus providing completely working recurves to reduce the shock of release at the grip and permit use of a shorter bow than has previously been possible.

It is accordingly an object of my invention to provide an improved laminated archery bow construction.

Another object of my invention is to provide an improved wood core for a laminated archery bow.

A further object of my invention is to provide an improved laminated archery bow construction incorporating a single-thickness wood core and in which additional material is not required at the recurves.

Further objects and advantages of my invention will become apparent by reference to the following description and the accompanying drawing, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

I have found that by providing a core comprising an elongated element formed of a plurality of wood segments joined end-to-end by joints respectively lying in planes defining an acute angle with the sides of the core, the ad dition of material at the recurves is not necessary, thus providing a completely working recurve and distributing the energy of release throughout the limbs, thus reducing shock at the grip, tiller of the recurves is substantially eliminated, and chrysal at the recurves is likewise substantially eliminated.

In the drawings:

FIG. 1 is a side View of an unstrung laminated archery bow of the recurve type incorporating my invention;

FIG. 2 is a side View of the bow of FIG. 1 when strung;

FIG. 3 is a side view of the improved core construction of my invention;

FIG. 4 is a top view of the core of FIG. 3;

FIG. 5 is a fragmentary view in perspective illustrating the method of making the core of FIGS. 3 and 4-; and

FIG. 6 is a fragmentary enlarged side View of the recurve of the bow of FIGS. 1 and 2.

Referring now to FIGS. 1 md '2 of the drawings, there is shown a bow generally identified at 1th and having top and bottom portions 112 and 14 joined to grip 16. The top and bottom portions 12 and 14 respectively include limb sections 1%, 2d and recurve sections 22, 24 terminating in top and bottom ends 26, 23.

Each of the portions l2, I4 is formed of a single thickness woo-d core 3d having single-thickness laminations 32 and 34 formed of suitable plasitc sheet materials such as fiber glass-reinforced polyester resin, respectively glued to the front and back sides of the core 31).

It will be seen that the wood core 30 extends into the grip 16, having additional wood laminations 36 which form the grip glued thereto, as shown. It will be seen that the back plastic lamination 34 leaves the core 30 at the grip forming the back surface of the grip whereas the front plastic lamination 32 is coextensive with core 30 with additional wood laminations 33 of the grip being glued to its outer surface, as shown. It will be seen that the unstrung bow of FIG. 1 assumes the configuration shown in FIG. 2 when bowstring 4-0 is strung thereon.

Referring now additionally to FIGS. 3 and 4 of the drawings, each core 36) in accordance with my invention is formed of a plurality of wood segments 42, which may be of random width, extending transversely across the core md joined end-to-end by glued joints 44 which respectively lie in parallel planes defining an acute angle with the fiat sides of the core. As seen in FIGS. 1 and 2, the joints 44 preferably are inclined downwardly toward the grip 16 from the back to the front side of the core. In the preferred embodiment of my invention, the joints 44 are inclined at an angle approximately 45 with respect to the flat sides of the core, however I have found that satisfactory results are obtained with a range of angles between approximately 30 and approximately 70 of downward inclination with respect to the sides of the core.

The segments 42 of core 30 may be formed of any dense grained wood of the type normally used for bow constructions, such as rock maple, birch or lemon wood. The end-to-end lengths of the segments 42 may vary from one inch to two and one-half inches. Any suitable glue may be employed which is moisture-proof and fungusresistant. t

. In order :to fabricate the core 30, I provide a plurality of planks 46 of suitable wood with the grain running lengthwise as shown by the arrow 48. These planks are glued side-to-side as at 50 with their ends 52 being staggered in the interest of saving material as shown. Parallel saw cuts 54 are then made at the desired angle 56 with reference to the side of the planks 46 to providethe core 30. It will thus be seen that in each of the segments 42 of the cores 3% the grain of the wood will be parallel, with the joints 44.

The cores 39 are preferably thicker near the grip and their edges also preferably taper from the grip end to the outer end. Thus, after sawing the cor-es 30 from the planks 46 as above described, the sides are preferably sanded from the flat parallel configuration shown by the dashed line 5% in FIG. 3 to provide the requisite tapering configuration. Likewise, the side edges 60 are preferably sawed and sanded from the configuration shown by the dashed lines 62 in PEG. 4, this tapering being referred to as tillering. In a specific embodiment of my invention incorporated in a sixty pound bow having an overall length of four feet ten inches (4'l0), the cores 30 were one and seven-eighths (1%) inches wide at the grip, five-eighths inch wide at the ends, the cores having a thickness of .165 inch at the grip and .135 inch at the ends and an overall length of twenty-one (21) inches respectively. In this specific embodiment, the back fiber glass lamination 32 has a thickness of .060 inch and the front laminaiton 34 a thickness of .055 inch.

Referring now specifically to FIG. 6, in prior laminated 3 bows known to the present applicant incorporating the conventional laminated wood core without the provision of additional laminations at the recurve, there is a tendency after use for the glue joining the wood laminatioris and also the fiber glass laminations to the wood core to degenerate and for the laminations to separate. Inspection of FIG. 6 will reveal however, that with the joints 44 being inclined downwardly from back to front, the core is in essence articulated with the joints bending with the core throughout the length of the recurve 22 as it is flexed from its normal position shown in solid lines to its drawn position as shown in the dashed lines 64. It will be readily apparent that if the segments 42 were joined by butt joints, i.e., joints extending in planes perpendicular to the sides of the core, there would be a tendency for the segments to tear apart at the joints, particularly at the recurve since the greatest flexing occurs at the recurve. However, the provision of the angled glued joints 44 provides greater glue area and I have found that when a bow incorporating my improved core 7 construction is distorted to the point of actual fracture, the break occurs not at one of the glued joints 44, but in a portion of a segment intermediate the glued joints.

It will now be seen that my improved bow construction, by incorporating a wood core 30 having a single thickness in the limbs and recurve portions, reduces the cost of the bow by eliminating the necessity for laminating the core and further permits straighter recurves which do not set up out of tiller. Since my improved bow construction does not require the employment of additional material at the recurves, the recurves have greater resilience and flexibility and thus provide greater working in the recurves rather than transferring the bending or flexing to the limbs. Thus,- upon release, the energy is distributed and dissipated throughout the entire length of the limbs, thus substantially reducing the shock or release at the grip; as a result of this reduced shock, the archer isc'apable ofbett'er marksmanship, sighting and arrow flight. Further by virtue of the even distribution of the energy of release from the ends to the handle, the I cast of the arrow is improved since the release is even and smoothrather than jerky. By virtue of the reduction in shock at the grip and the even distribution of the energy released, a much shorter how can be provided for the same poundag'e of thrust, i.e., a sixty (60) pound bow four feet six inches (46) long can be provided incorporating my'invention as opposed to a conventional laminated b'ow'of the same poundage which is five foot four inches ('4") long. My improved construction further provides su'bstantial reduction in breakage or chrysal in the laminations, particularly at the recurves.

' While I have illustrated and described a specific embodiment of my invention, further modifications and improvements will occur to those skilled in the art and I desire therefore in the appended claims to cover all modifications which do not depart from the spirit and scope of my invention.

What is claimed is:

1. In a laminated archery bow having a core formed of wood and laminations of plastic material adhered thereto: the improvement wherein said core comprises an elongated element having flat opposite sides, each of said sides defining a single elongated continuous surface, said element being formed of a plurality of wood segments. joined end-to-end by joints respectively lying in planes defining an acute angle with said sides.

2. In a laminated archery bow having a core formed of wood and laminations of plastic material adhered thereto; the improvement wherein said core comprises an elongated 4 element having flat opposite sides, each of said sides defining a single elongated continuous surface, said element being formed of a plurality of unitary wood segments joined end-to-end by glued joints respectively extending transversely across said element and lying in planes defining an acute angle with said sides.

3. The combination of claim 1 wherein said angle is between approximately 30 and 4. The combination of claim 1 wherein said angle is approximately 45.

5. The combination of claim 1 wherein the grain of the wood of each segment is parallel with said planes.

6. In a laminated archery bow having a core formed of wood and laminations of plastic material adhered thereto; the improvement wherein said core comprises two elongated elements, each element having a generally rectangular cross-section with flat opposite sides and opposite edges, said sides and edges being respectively tapered from one end of said element to the other end whereby each element is wider and thicker at said one end at said other end, each element being formed of a plurality of unitary wood segments each extending transversely across said element, said segments being joined end-to-end by glued joints respectively extending transversely across said element and lying in planes defining an acute angle with said sides.

7. In a laminated archery bow having top and bottom ends, front and back sides, a grip intermediate said ends, and a core formed of wood with laminations of plastic material adhered thereto; the improvement wherein said core comprises two elongated elements respectively terminating in said ends and joined to said grip, said elements respectively having flat front and back sides, said elements being respectively formed of a plurality of wood segments joined end-to-end by joints respectively lying in planes which are inclined downwardly toward said grip from said back to said front sides.

8. The combination of claim 7 wherein said inclination is at an angle between approximately 30 to 70 with respect to said back side.

9. In a laminated archery bow of the recurve type having top and bottom portions joined by a grip, each portion having a limb section adjacent said grip merging with a recurve section which terminates in the end of the respective portion, each portion having a core formed of wood with flat front and back sides and with lamination's of plastic material respectively adhered thereto, the improvement wherein each core comprises an elongated single-thickness element formed of a plurality of unitary wood segments each extending transversely across said element, said segments being joined end-to-end by glued joints respectively extending transversely across said element and lying in planes which are inclined downwardly toward said grip from said back to said front sides of said core, and wherein each said lamination of plastic material is a single thickness and extends unitarily from said grip to the end of the respective portion.

References Cited by the Examiner UNITED STATES PATENTS 2,525,618 10/50 Pierce 280-1113 2,945,488 7/60 Cravotta et al. l24''-23 LEONARD W. VARNER, RICHARD o. PINKHAM, Exami e s UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ,167 ,063 January 26, 1965 Nick Kappas It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4, line 21, before "at" insert than Signed and sealed this 3rd day of August 1965.

(SEAL) Auest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. IN A LAMINATED ARCHERY BOW HAVING A CORE FORMED OF WOOD AND LAMINATIONS OF PLASTIC MATERIAL ADHERED THERETO: THE IMPROVEMENT WHEREIN SAID CORE COMPRISES AN ELONGATED ELEMENT HAVING FLAT OPPOSITE SIDES, EACH OF SAID SIDES DEFINING A SINGLE ELONGATED CONTINUOUS SURFACE, SAID ELEMENT BEING FORMED OF A PLURALITY OF WOOD SEGMENTS JOINED END-TO-END BY JOINTS RESPECTIVELY LYING IN PLANES DEFINING AN ACUTE ANGLE WITH SAID SIDES. 